Columbia Cross Train 700c Men's 21-Speed Fitness Hybrid Commuter Bike Manufactured Light weight Alloy frame for long-lasting durability 21 Speed flat bar road bike and hi-tensile steel forks to maximize stability and control Accessorized with back and front alloy V-brakes (direct-pull rim brakes) and Shimano RAPIDFIRE Shifter and RD-TZ31 Rear Derailleur Featuring upright ergonomics both in the saddle (seat) and the style of this bicycle are built for comfort and ease 18-inch frame fits most riders between 5'5'' and 5'11''